Resize images using Imagemagick

Install Imagemagick from the repo and run the following to get the size of the image:

identify -format "%wx%h" image.jpg

Then run the following to adjust the size proportionally. The height is fixed, the width is flexible:

convert image.jpg -resize 600x400\> image.jpg

References: https://guides.wp-bullet.com/batch-resize-images-using-linux-command-line-and-imagemagick/